Along with improvement in performance of high-end computers such as a supercomputer, large-scale application programs such as a heat conduction simulation, a typhoon simulation, and a simulation of a flow around a body have been executed at high speed and resolution.
In such a large-scale application simulation, computational results are successively output and accumulate considerably. In general, in the applications of the heat conduction simulation and the typhoon simulation, an amount of data output at each time step is calculated by “mesh size of target physical area for calculation×the number of time steps×the number of physical quantity types”.
For example, provided that the mesh size of the three-dimensional area is 10,000×10,000×10,000, the number of time steps is 100,000, and 100 types of 8-byte physical quantity are set, the total size of output data equals 805 petabytes.
To store such an enormous quantity of output data, a considerable disk capacity is required. Further, such output data is input to a visualizing device (display device) and used to display a simulation process. Because of the huge data amount, a processing time necessary to display the data is increased. Thus, it is necessary to save a requisite disk capacity and in turn to reduce a visualization load by reducing output data.
As a method for reducing spatial data as above, a method for storing output data about a simulation at certain regular time-step frequency (thinning out data on a time axis), and a method for storing output data about a simulation at certain regular area frequency (thinning out data on an area axis) are proposed. These methods are discussed in Japanese Patent Application Laid-open No. 2005-198266 and Japanese Patent Application Laid-open No. 2006-303690.